Poland is ready to defend its decision in the European Union's top court to refuse to accept migrants from Africa and the Middle East under an EU plan to redistribute them, Deputy Foreign Minister Konrad Szymanski said.

He spoke after the EU executive sued Poland, Hungary and the Czech Republic in the European Court of Justice on Thursday for their refusal to host these migrants.

"Poland is ready to defend its position in the Court," Szymanski told state news agency PAP. "No one will lift the duty of providing public safety from the Polish government."

The government of Poland's right-wing Law and Justice (PiS) party has said it will not admit migrants, citing security concerns amid deadly Islamist attacks in western Europe and problems with ascertaining the identify of migrants.

The Foreign Ministry said on Wednesday it had signed a deal with the European Investment Bank to give 50 million euros to help countries and territories affected by the migration crisis, mainly Lebanon, Jordan and the West Bank.

Foreign Minister Witold Waszczykowski said that Poland — a country of 38 million — is already hosting migrants as it had issued more than a million work permits for people from neighboring Ukraine last year alone.